The present invention is directed to a vane inlet apparatus, and more particularly, to a cylindrically-shaped vane inlet apparatus for more efficiently separating the components of a feed stream.
Devices are used in industry to separate a feed stream into its components, which often include at least liquid and gas. Such devices are typically used in large tanks and are fed by cylindrical pipes through which a feed stream travels at an extremely high velocity. The device receives the feed stream and a plurality of vanes redirect the flow. As the feed stream enters the tank and is redirected by the vanes, the liquid tends to separate into droplets that settle into the tank while the gas rises above the liquid. While such devices and the processes for utilizing same are well known, they suffer from major inefficiencies due to the structure and design of the existing devices.
Current devices utilize two rows of vertically-oriented vanes, one row positioned along each side of the chamber to redirect flow from the chamber toward each side of the device. Thus, while the pipes and the inlets of the devices are circular in cross-section, the chambers are typically rectangular in cross-sections with vanes that have substantially vertical leading edges. As the flow of the feed stream is circular in cross-section, the vertically-oriented vanes are unevenly contacted by the feed stream along the length of the device. The vanes nearer to the inlet of the device slice off smaller portions of the feed stream than do the vanes further from the inlet. Moreover, the four corners of a rectangular cross-section of the chamber would receive little to none of the feed stream. As a result, the more distal vanes along the direction of flow bear the brunt of the feed stream and tend to distribute the incoming fluids less uniformly. This all contributes to an inefficient use of the device, resulting in less efficient separation of the components of the feed stream. Moreover, the large cross section of the existing devices blocks off a substantial portion of the tank area, causing higher pressure drop and locally higher turbulence, which decreases the effectiveness of the device.
Existing devices are also very cumbersome to manufacture and assemble. The nature of the vanes and their positioning in the chamber requires a large number components and small parts such as bolts and washers to secure the vanes within the device. Moreover, the rectangular design of the devices requires that they be assembled from within the tank, process vessel, or column in which they are to be used. This requires one or more workers to risk injury by entering the process vessel during assembly. In addition, existing devices are difficult to retrofit into existing older process vessels, because either internal weld attachments must be added, affecting ASME Section VIII Pressure Vessel Code integrity, or a complex system of expanding, clamping rings and/or struts must be fitted and installed, the purpose of such weld attachments and clamping devices is to support the prior art device(s) inside the vessel.
Therefore, a need exists for a vane inlet device that separates the components of a feed stream more efficiently and that is more economical and simpler to manufacture, assemble, and install through the cylindrical inlet opening of the vessel.